Statements that Manipulate Default Values

Default values can be created, altered, and deleted with the following statements:

• CREATE TABLE (in the column definition)
• ALTER TABLE (Column)
  • ADD COLUMN (in the column definition)
  • MODIFY COLUMN (in the column definition)
  • ALTER COLUMN DEFAULT with SET DEFAULT or DROP DEFAULT

Default values are explicitly or implicitly used in tables with the following statements:

• INSERT: DEFAULT as a 'value' from a column (INSERT INTO t(i,j,k) VALUES (1, DEFAULT, 5)) or DEFAULT VALUES for all columns (INSERT INTO t DEFAULT VALUES) or implicitly at column selection (for the columns that were not selected)
• IMPORT: implicitly at column selection (for the columns that were not selected)
• UPDATE: DEFAULT as a 'value' for a column (SET i=DEFAULT)
• MERGE: DEFAULT as a 'value' for column in the INSERT and UPDATE parts or implicitly in the INSERT part at column selection (for the column that were not selected)
• ADD COLUMN: if a default value was specified for the inserted column with DEFAULT